Prime Minister Jacinda Ardern has again been name-checked in a Democratic Presidential debate in the US but this time, it was by a much more high-profile candidate.

Pete Buttigieg – Mayor of the Indiana town of South Bend – cited the Kiwi Prime Minister when he was asked a question about his age.

At 37, Buttigieg is the youngest candidate running for President – a recent New York Timespoll put him at fifth place, behind the likes of former Vice President Jo Biden and Bernie Sanders.

But Buttigieg does not think his age is an issue.

"I don't care how old you are. I care about your vision."

"I do think it matters that we have a new generation of leaders stepping up around the world leaders like the – I actually think it's good the Prime Minister of New Zealand has gotten a lot of attention in Democratic debates.

"She's masterful, she's younger than I would be when I take office.

This is not the first time Ardern has been name-checked by Buttigieg – he spoke about her during an interview with the New Yorker's David Remnick when talking about new-generation leaders.

It's not even the first time Ardern has been referenced during a Democratic Presidential debate.

Late last month, Marianne Williamson, a self-help author and spiritual guru who has never held office, turned to New Zealand when asked who the first person she'd contact from the Oval Office would be.

"My first call is to the Prime Minister of New Zealand, who said that her goal is to make New Zealand the place where it's the best place in the world for a child to grow up," Williamson said.

"I would tell her: 'girlfriend, you are so on', because the United States of America is going to be the best place in the world for a child to grow up."

Asked about the reference, Ardern said it was an "unusual reference".

But she said if another country has the same ambition as New Zealand does for children, "that's a great thing".

Asked which country was a better place to grow up, Ardern said: "Of course I would say New Zealand".

"But that's not to say there aren't things we can do better.

"My measure is not so much the league tables of the world, but whether our children themselves are having a great experience growing up here."